Rounding Calculator
Free rounding calculator. Round any number to a set number of decimal places, significant figures or the nearest multiple, using round, floor, ceil or truncate.
Input
Rounded Result
3.14
Details
How It Works
Enter your number
Type the value you want to round, including a decimal point or minus sign if needed.
Pick a mode & precision
Choose to round to decimal places, significant figures or the nearest multiple, then set the precision or multiple.
Choose a method
Select round half up, floor, ceil or truncate, and read the rounded result instantly.
Rounding replaces a number with a nearby, simpler value so results are easier to read, report or use in measurements. The right approach depends on context: prices round to two decimal places, scientific measurements round to a fixed number of significant figures, and quantities often round to the nearest convenient multiple such as 5, 10 or 100.
This calculator covers all three approaches and lets you control how the rounding happens. Choose round half up for ordinary nearest-value rounding, floor or ceil to force a direction, or truncate to chop digits without rounding. Combine any method with decimal places, significant figures or a custom multiple to get exactly the result you need.
Frequently Asked Questions
What is the difference between decimal places and significant figures?
Decimal places count digits after the decimal point — 3.14159 to 2 decimal places is 3.14. Significant figures count all meaningful digits from the first non-zero digit — 0.0031847 to 2 significant figures is 0.0032. Significant figures track precision regardless of where the decimal point sits.
What do the rounding methods mean?
Round half up rounds to the nearest value and sends exact halves upward. Floor always rounds toward negative infinity, ceil always rounds toward positive infinity, and truncate simply drops the extra digits toward zero without any rounding.
How do I round to the nearest multiple?
Rounding to the nearest multiple snaps a number to the closest multiple of a value you choose — for example rounding 47 to the nearest 5 gives 45, and to the nearest 10 gives 50. The calculator divides by the multiple, rounds with your chosen method, then multiplies back.
Does this handle negative numbers?
Yes. Negative numbers are supported in every mode. Be aware that floor and ceil behave by direction on the number line, so flooring -2.3 gives -3 while truncating it gives -2.
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